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Features - hi-rez USB: To test the DAC2 with high-resolution 24/192 Flac files purchased online from Linn Records, I first had to convert them to Aiff to play inside iTunes. When the Switch software didn't work out, this Mac virgin wasn't keen to install Fluke or Max instead. El principiante ensangrentado (bloody novice) then read that Amarra 2.0 converts Flac files on the fly and accesses them through the 'open files' command in the new playlist feature. Still not keen on paying CHF823 for the privilege, there also was the promise to improve standard 16/44 playback. Sometimes taking one for the team is required.


After purchasing a full copy with USB dongle from Daniel Weiss of Weiss Engineering, I realized that Amarra 2.0 can permanently rewrite Flac files to Aiff individually or as a whole folder.


This neatly imports your hi-rez albums into iTunes' regular interface. Such conversion of course wasn't instantaneous. Even individual high-resolution tracks are sizeable. Still, 10 minutes after prompt, a complete hi-rez album with cover art like the above had installed in iTunes. While regular Mac users achieve this with freeware to shake their heads, I took the easy but expensive way out. Whether Amarra actually sounds better on 16/44 I'll leave for another day.


To give you a very practical example of file sizes involved, Maximiliano Martin's Vibraciones del Alma album is 2.149MB as a 24/192 Flac file, half that as a 24/88.2 Flac/WMA version. The standard 16/44 Redbook file in Flac or WMA is a mere 222.6MB and MP3 320K is half that. The data density of 24/192 is thus roughly 10 times that of ordinary CD and 20 times higher than the lowest-loss MP3 compression. Amarra 2.0 also plays Apple Lossless files downloaded from the iTunes store. If you don't care for Amarra's silly output meter dance, select hide mode [below]. This reduces Amarra's graphic presence to a small square icon in the dock. A blue dot on the icon signifies Amarra playback, yellow is for iTunes. Amarra's remote function enables Apple's little white wand so you don't lose that functionality.

Switching between Amarra/iTunes is instant and aside from the little icon, your display looks and works exactly like iTunes pure [above]; except that higher-rez files play back in native resolution without Audio Midi resets. With both Minerva and DAC2, this prompted immediate hardware adjustments to match the higher sampling rates. (It also meant that with Amarra, Redbook files locked the Minerva to 44.1 whereas in iTunes, any of its sampling rates remain selectable through the Weiss software in the Applications folder.) Depending on file format, the DAC2 set itself to USB96k and USB192k and back to 44k1 in a jiffy. This mirrored how changing S/PDIF output rates earlier had prompted the DAC2 to follow when it was leashed to the Minerva. In short, the USB 24/192 feature worked exactly as advertised.

Features - amp-direct drive: As I'd already tested in my review of Yamamoto's passive AT-03-1A controller, the variable gain feature of the DAC2 was superior to running through an ultra-purist passive whose lack of output stage seemed less happy driving a one-meter interconnect than the Wyred was driving a 4-meter equivalent. Quoting from that review, "...both converters quite upset the defamation league where 'd' stands for digital [attenuation]. The Weiss DAC2 in variable mode offers no numerical confirmation of chosen volume. That's been added since to the far costlier DAC 202 model. The W4S at my chosen playback level showed about 25dB of digital attenuation. This matched the Yammy's own calibration in the analog counter session. With max output voltages for both converters identical, standard listening levels saw them set inside a roughly minus 20-30dB window.


"Going amp direct was superior - more clarity, more immediacy, more energy and transient precision... Amp-direct sounded very much like improved drive control; as though the amplifier was much happier coupled to the DACs' output stages than the passive box. Making this connection an actual explanation—that the DACs' output stages had superior drive and control—is mere assumption. Not debatable was the audible superiority and its flavor which is very adequately encapsulated by the word direct itself. In short, wholesale condemnation of digital attenuation would seem a bit old-fashioned and shortsighted. Perhaps it was true once. It's likely still true if engaged so steeply that resolution decimation crosses the critical threshold..."

Wadia of course has championed digital attenuation ages ago already. Most audiophiles simply never adapted because the mere concept of throwing away resolution to control volume seems antichrist to our high-fidelity worship. With today's 24- and 32-bit silicon however, there's plenty of built-in throwaway headroom before one decimates actual 16/44 data. 'Common' sense had me too assume that Yamamoto's pure analog solution would prove superior in the above sessions. Listening put a lie to that notion. Obviously one wants to match system gain requirements to the DAC2's output voltage such as to minimize how much digital attenuation has to occur. At -25dB with the 98dB Voxativ Ampeggio widebanders and hi-gain Yamamoto SET, I didn't hear any negatives.

For some practical figures, my usual 91dB ASI Tango R speakers with the 25wpc FirstWatt J2 sat at ca. minus 15 to 20dB for customary levels. My stunning white Trafomatic Kaivalya tube monos with 25 watts per side but deliberately low 3V input sensitivity sat at minus 15 to 5dB. The latter got loud even with classical material of low recorded median level. Depending on how far or close your DAC2 will sit from the listening chair—and whether your eye sight still is what it once was—you could find its display for these volume adjustments a bit small. Otherwise this feature also worked exactly as advertised. It's no bling item to jack up the price. It's a true benefit if one mustn't accommodate analog sources like a tuner or turntable.


Before we close this chapter, it'd be irresponsible and deceptive of me to make any categorical statements of direct-drive superiority. Lean, mean and straight to the bean is how I'd called the scheme in the Yamamoto review. For the widebander combo with direct-heated premium triodes, it was what the doctor ordered to not slow down and fatten up the tremendously attractive lucidity of that system. Ditto for my IT-coupled push/pull Kaivalya EL84 monos into the Tangos. Those amps' THD behavior was very carefully trimmed with two local feedback loops (0.3/4dB respectively) to not want any flavorization - just an invisible means to control volume. For these applications, eliminating even a luxurious $10.000 preamp like my cherished Esoteric C-03 set to zero gain was the silver bullet. I admit that analog supremacy has seen better days but there it is. However - for the J2 or F5/Tango combos, many listeners not on my particular adrenaline leanness/luminosity kick would have preferred the Esoteric with 12dB of gain to make things a bit fleshier.
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